UITextfield keyboard with only alphabet, no numbers, no caps, no spacebar?

Question

I want the keyboard for the UITextfield to only have a-z, no numbers, no special characters (!@$!@$@!#), and no caps. Basicly I am going for a keyboard with only the alphabet.

Answer 1

class ViewController: UIViewController,UITextFieldDelegate {  

     @IBOutlet var phoneTextField:UITextField!

    override func viewDidLoad() {
            super.viewDidLoad() 
    self.phoneTextField.delegate = self
    }

     func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool
           {
                let textString = (textField.text! as NSString).replacingCharacters(in: range, with: string)

                if textField == self.phoneTextField  && string.characters.count > 0 {
                    let LettersOnly = NSCharacterSet.Letters
                    let strValid = LettersOnly.contains(UnicodeScalar.init(string)!)
                    return strValid && textString.characters.count <= 10
                }
                return true
            }
    }

Try this code
In above code is only allow 10 char in text field

Answer 2

An easiet way would be:

if let range = string.rangeOfCharacterFromSet(NSCharacterSet.letterCharacterSet())
    return true
}
else {
    return false
}

Answer 3

if isValidInput(Input: yourtextfieldOutletName.text!) == false {
    let alert = UIAlertController(title: "", message;"Name field accepts only alphabatics", preferredStyle: UIAlertControllerStyle.alert)
    alert.addAction(UIAlertAction(title: "Ok", style: UIAlertActionStyle.default, handler: nil))

    self.present(alert, animated: true, completion: nil)
}

func isValidInput(Input:String) -> Bool {
    let myCharSet=CharacterSet(charactersIn:"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
    let output: String = Input.trimmingCharacters(in: myCharSet.inverted)
    let isValid: Bool = (Input == output)
    print("\(isValid)")

    return isValid
}

Answer 4

Swift 4.2 Code Allow only alphabets with allowing backspace if the user wants to remove wrong character

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
    if string.rangeOfCharacter(from: .letters) != nil || string == ""{
        return true
    }else {
        return false
    }
}

Answer 5

Update for those who wants to Allow Space, Caps & Backspace Only

Swift 4.x, Swift 5.x & up

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

    if range.location == 0 && string == " " { // prevent space on first character
        return false
    }

    if textField.text?.last == " " && string == " " { // allowed only single space
        return false
    }

    if string == " " { return true } // now allowing space between name

    if string.rangeOfCharacter(from: CharacterSet.letters.inverted) != nil {
        return false
    }

    return true
}

Answer 6

Swift 3 solution

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {

     let characterSet = CharacterSet.letters

     if string.rangeOfCharacter(from: characterSet.inverted) != nil {
         return false      
     }
     return true
}